Electric timepiece movement



May 21', 1946. DALES 2,400,687

ELECTRJ EC TIME PIECE MOVEMENT Filed April 10, 1941 INVENTOR GEORQLFRANKL/N DALES .n: 9/ 'IY 89y ATTORNEYS) Patented May 21, 1946 ELECTRICTIMEPIECE MOVEMENT George Franklin Dales, Akron, Ohio, assignor ofone-third to Alton R. Wells, Akron, Ohio Application April 10, 1941,Serial No. 387,825

4 Claims.

This invention relates to a novel movement for electric watches orclocks. The movement is illustrated for use with a small dry cellbattery, but it will function equally well with other sources ofcurrent.

An object of the invention is to employ novel means for use in all typesof time pieces for controlling the timing and the length of the impulseas well as the manner of imparting the impulse given to the oscillatingmember, which may be a wheel or pendulum.

Another object is to provide a movement of the character referred towhich is simple, reliable, accurate, and eflicient, as well aseconomical.

A further object is to provide an oscillating member carrying anarmature, which member, in the illustrated form of the invention, isrotated in one direction by an electro-magnet attracting said armatureand in the opposite direction by the force of gravity or some equivalentmeans. In the illustrated form of the invention the oscillating membercontrols the operation of a switch closing arm which intermittentlycloses a circuit through one or more electromagnets to keep the movementin operation.

A further object is to provide a ratchet wheel adapted to be connectedto a gear train for operating the hands of the time piece and to movethe ratchet wheel by a pawl connected to and operated by the oscillatingmember.

A further object is to provide a switch closing arm or member in theform of a bar fixed at one end, and to provide means engaging said baradjacent its opposite end for preventing excessive vibration of saidbar.

Other objects and advantages will become apparent from the followingdescription taken in conjunction with the accompanying drawing.

In the drawing:

Fig. 1 is a partial side elevation of one form of the invention omittingthe train of gears which operates the hands,

Fig. 2 is a fragmentary view with the mechanism in a different position,and

Fig. 3 is a fragmentary top plan View.

Referring to the drawing the pendulum or oscillating member 8| ismounted for oscillation on a shaft 82 suitably mounted in the frame. Theoscillating member 8| in this instance comprises a weighted dependingarm 83 and a small arm 84 extending upwardly. Arm 83 carries an armature85 intermediate its ends which is adapted to be attracted by the core 86of an electro-magnet 81 when the latter is energized.

Arm 83 also carries a pin 88, projecting forwardly therefrom as viewedin Figs. 1 and 2, and the oscillations of the member 8| cause pin 88 toengage a projection 89 on the spring bar 99 in a manner to be described.In this form of the invention projection 89 is located intermediate theends of bar 90 and is tilted slightly out of the plane of bar 90 asindicated. Bar 90 is fixed at one end 9| to the frame and the oppositeend 92 rests upon a cork bumper 93 which acts as a damper to preventexcessive vibration of the bar. Bar 99 also carries a switch arm 93which is adapted to be moved by pin 88 from the position shown in Fig. 1to switch closing position with a switch member 94 as indicated in Fig.2. Member 94 is secured to the frame and insulated therefrom and has anoutwardly projecting portion 95 against which arm 93 makes contact.

Arm 84 has a pin 99 extending outwardly therefrom which carries one endof a spring arm or other rigid member 91 having a pawl 98 on its outerend to engage the teeth of a ratchet wheel 99 mounted for rotation inthe frame. Ratchet wheel 99 operates the customary gear train foractuating the hands of the time piece, as will be understood, but sincethis gear train forms no part of the present invention, it has not beenillustrated. Only a small number of teeth are shown on the ratchet wheeland it is preferred that there be or some multiple thereof, such as 120.Ratchet wheel 99 is adapted to be moved in a counter-clockwise directionas viewed in Figs. 1 and 2 and a plate spring I08 is arranged to preventrotation of the ratchet wheel in the opposite direction.

The circuit shown in Fig. 1 comprises a source of electric current llll,which may be either a small dry cell battery or some other source, fromwhich a conductor I02 leads to the switch member 94. A second conductorI93 also leads from the source of current to one terminal of theelectro-magnet 81, and the other terminal of said electro-magnet has aconductor I94 leading therefrom to be grounded to the frame as at I95.Since end 9| of arm is in engagement with the frame, it will be apparentthat a circuit will be closed through the electro-magnet whenever switcharm 93 is in engagement with switch member 94.

In operating the mechanism shown in Figs. 1 to 3 the oscillating memberis first moved manually from the full line position to about the brokenline position shown at the left in Fig. 1, in which position pin 88 willbe out of engagement with projection 89 on bar 99. As the oscillatingmember swings from the latter position toward the right, pin 88 willengage projection 89 on its lower surface and move arm 93 intoengagement with switch member 94, as shown in Fig. 2, to close thecircuit and energize electro-magnet 81. Core 86 of the latter will thenattract the armature 85 and pull the oscillating member toward theright. The oscillating member will continue its move ment toward theright to approximately the dash line position shown in Fig. l. Theoscillating member will then return to the left and during this returnmovement pin 88 will engage the upper surface of projection 89, movingarm 93 further away from switch closing position than it was initially,but after pin 88 has passed across said upper surface, bar 90 and arm 93will return to the position shown in Fig. 1. After completing itsmovement to the left the oscillating member will again swing to theright and the movement will be continuous, as will be understood.

During the movement of the oscillating member from left to right thecore 86 is energized just prior to the time the oscillating memberreaches the position shown in Fig. 2, and it becomes de energized justat the time the oscillating member reaches the full line position shownin Fig. l, which is its vertical position. Thus there is no tendency forthe electro-magnet to attract the armature 85 as the oscillating membermoves from its vertical position toward the right, and hence no tendencyto slow down the movement of the oscillating member toward the right.

Each time the oscillating member swings from left to right, arm 84 movesin the opposite direction and causes pawl 99 to engage one of the teethon ratchet wheel 99 to rotate the latter counter-clockwise. Thus, themovement of the ractchet wheel in this form of the invention iscontrolled directly from the oscillating member. When 60 teeth are usedon the ratchet wheel, the movement need only be /60 of a revolution, orone tooth per second, and when 120 teeth are used, the movement needonly be /120 of a revolution, or two teeth per second. This slowermovement reduces wear on the pivots, simplifies the movement, givesgreater efiiciency and thereby requires less operating power.

It will be apparent that the features described are well calculated tocarry out the objects of the invention and to provide a movement whichis at all times satisfactory.

This invention has many advantages over prior time piece movements. Forexample, the operating power required for the new movement is verysubstantially less than that heretofore required. The number of movingparts previously required has been materially reduced so that theelimination of friction losses which would be present by using suchparts and the simple manner of imparting a periodic impulse to a freeswinging oscillating member requires but a small amount of current. Thisfactor makes possible a practical electrical movement having aself-contained battery for even small watch units. By using conventionalresistance and relays, the movement may be adapted for operation upon acustomary 110 volt A. C. current or upon as little as 3 volts A. C.current, as well as upon a one and one-half to four and one-half volt D.C. current.

Some other features and advantages are that my movement provides freedomfrom continuous A. C. hum which is a fault of a regular A. C. timepiece. A reasonable amount of tilting of the time piece is alsopermissible with my movement, even when a pendulum is used as theoscillating member. Also, there is present a very high degree ofisochronism, i. e., whether the battery is fully charged or nearlyexpended, the speed of the oscillating member is the same, although thedistance it moves may be varied.

While I have illustrated and described one form of my invention it willbe apparent that changes and modifications may be made therein withoutdeparting from the spirit of the invention or from the scope of thesubjoined claims.

What is claimed is:

1. In an electric time piece, an oscillating member, an armature carriedby said member, switch operating means also carried by said member, anelectro-magnet adapted to attract said armature, a ratchet wheel,ratchet wheel operating means carried by said member, means forenergizing said electro-magnet, and a movable switch member arranged inthe path of travel of said oscillating member and adapted to close acircuit through said energizing means, said switch member having aprojection intermediate its ends, one side of which is engageable bysaid switch operating means when said oscillating member moves in onedirection, the other side of said projection being engageable by saidswitch operating means when said oscillating member moves in theopposite direction, said switch member comprising a bar fixed at oneend, and means engaging said bar adjacent its opposite end forpreventing excessive vibration of said bar.

2. In an electric time piece, an oscillating memher, an armature carriedby said oscillating member, switch operating means also carried by saidoscillating member, an electro-magnet adapted to attract said armature,a ratchet wheel, ratchet wheel operating means carried by saidoscillating member, means for energizing said electro-magnet, and amovable switch member arranged in the path of travel of said oscillatingmember and adapted to close a circuit through said energizing means,said switch member comprising a bar fixed at one end, and means engagingsaid bar adjacent its opposite end for preventing excessive vibration ofsaid bar.

3. In an electric time piece, an oscillating member, an armature carriedby said oscillating member, switch operating means also carried by saidoscillating member, an electro-magnet adapted to attract said armature,a ratchet wheel, ratchet wheel operating means operative in timedrelation with said oscillating member, means for energizing saidelectro-magnet, and a movable switch member arranged in the path oftravel of said oscillating member and adapted to close a circuit throughsaid energizing means, said switch member comprising a bar fixed at oneend, and means engaging said bar adjacent its opposite end forpreventing excessive vibration of said bar.

4. In an electric time piece, an oscillating member, an armature carriedby said oscillating member, switch operating means also carried by saidoscillating member, an electro-magnet adapted to attract said armature,means for energizing said electro-magnet, and a movable switch memberarranged in the path of travel of said oscillating member and adapted toclose a circuit through said energizing means, said switch membercomprising a bar fixed at one end, and means engaging said bar adjacentits opposite end for preventing excessive vibration of said bar.

GEORGE FRANKLIN DALES.

